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Statistical learning shapes face evaluation

The belief in physiognomy—the art of reading character from faces—has been with us for centuries. People everywhere infer traits (for example, trustworthiness) from faces, and these inferences predict economic, legal and even voting decisions. Research has identified many configurations of facial features that predict specific trait inferences, and detailed computational models of such inferences have recently been developed. However, these configurations do not fully account for trait inferences from faces. Here, we propose a new direction in the study of inferences from faces, inspired by a cognitive–ecological and implicit-learning approach. Any face can be positioned in a statistical distribution of faces extracted from the environment. We argue that understanding inferences from faces requires consideration of the statistical position of the faces in this learned distribution. Four experiments show that the mere statistical position of faces imbues them with social meaning: faces are evaluated more negatively the more they deviate from a learned central tendency. Our findings open new possibilities for the study of face evaluation, providing a potential model for explaining both individual and cross-cultural variation, as individuals are immersed in varying environments that contain different distributions of facial features.

If you have generated reverse correlation stimuli with my older python script and now want to analyze your data with the much more user friendly rcicr, feel free to download these two PythonR Conversion scripts.

Then follow these steps:

1) Make sure you have rcicr version 0.3.0 or higher installed. Currently, this means you have to install the development version (see here).

2) Adapt single_gzipped_pickle_to_csv.py to point to the right .pkl file generated with the reverse correlation python scripts (this is the file containing the contrast parameters for each stimulus and is also used in analysis) and run it. It will output a contrasts.csv file.

3) If your base image is not 256×256, 512×512, or 1024×1024, rescale it with any image editor your have available.

4) Then edit create_r_data_file.r. You only need to edit the lines between Customize below and Until here, and run it. Make sure the contacts.csv file and the base image jpg is in the working directory you specified. Run the script in R.

And you’re done. A new .rdata file is generated, which you can reference with rcicr.